Correct typo in docstring

Author: Tomas Lycken

src/scaling/scaling.jl

@@ -15,7 +15,7 @@ end
 end
 
 """
-`scale(itp, xs, ys, ...)` scales an existing interpolation object to allow for indexing using other coordinate axes than unit ranges, by wrapping the interpolation object and transforming the indices from the provided axes onto unit ranges upon indexing.a
+`scale(itp, xs, ys, ...)` scales an existing interpolation object to allow for indexing using other coordinate axes than unit ranges, by wrapping the interpolation object and transforming the indices from the provided axes onto unit ranges upon indexing.
 
 The parameters `xs` etc must be either ranges or linspaces, and there must be one coordinate range/linspace for each dimension of the interpolation object.